In recent years, WiMAX (Worldwide Interoperability for Microwave Access) has received attention as standard specifications for radio communication. WiMAX is standardized in IEEE802.16, IEEE802.16e, IEEE802.16 Corrigendum 2 and WiMAX Forum. In technologies which employ this standard, when a terminal such as SS (Subscribe Station) and MS (Mobile Station) accesses to a network, the terminal itself selects a base station (BS) to which it should connect, and then starts a network access procedure.
When a terminal attempts to connect to a base station, the connection of the terminal can be difficult depending on the radio resources of the base station. In this event, an access service network (ASN) has no ability to hand over the terminal to another base station during a network access procedure.
A technology has also been contemplated for notifying a terminal of a base station to which the terminal should connect, from a radio terminal connection device for controlling base stations, in accordance with a time zone in which the terminal connects to a base station, in order to avoid line shortage of a radio base station (see, For example, JP1998-23503A).
In the technologies described above, a network access procedure can fail due to the inabilities of the access service network (ASN) to hand over a pertinent terminal to another base station. Also, even if a base station exists with sufficient radio resources in the same coverage area as a pertinent base station, a problem arises in that the terminal cannot be guided to the base station which provides sufficient radio resources. Also, another problem arises in a situation where a plurality of base stations are installed to manage the same coverage area in which a hand-over procedure must be performed at the initiative of the base stations after completion of a network access procedure for each terminal, to hand over such terminals to respective base stations, in order to distribute terminals, which are gaining access to a network one after another, to respective base stations.
Also, in the technology disclosed in JP1998-23503A, since the connection of a terminal with a base station is managed in regard to time zones, it is necessary to previously set a time zone in which the terminal can connect to a predetermined base station, giving rise to a problem in which a considerable effort is required to complete the setup.